China’s rolling world single largest austenitic stainless steel ring forgings！

（HY workshop technician section）

On March 12, 2019, a giant aquarium forging of austenitic stainless steel with a diameter of 15.8 meters and a weight of 150 tons was completed in Jinan, Shandong Province. The super forgings adopted the international first metal forming technology and were the largest in the world by Elite. The 16-meter rolling ring rolling mill completed the rolling and successfully broke many world records: First, the first 200-ton metal billet was constructed and added, and the second was the world’s heaviest austenitic stainless steel forging; The third is to become the world’s largest diameter forging austenitic stainless steel ring.

Traditional large forgings are usually manufactured using the method of “large to large”, that is, the forged base metal must be larger than the molded workpiece. According to this process, the large forgings produced this time need to be poured into a single 250-ton steel ingot, but The casting quality of super large stainless steel ingots is unstable, and metallurgical defects such as shrinkage, element segregation and inclusions exceeding the standard are easily found inside the ingot, which makes the final forging quality difficult to meet the technical requirements.

In order to overcome this problem, since 2016, the team of Elite and Li has been the first in the world to develop the metal construction technology of “small system”, and has carried out 1/8 ratio, 1/3 ratio, and other sections. The simulations and other verifications were repeated, and the technical measures were continuously adjusted. Finally, in February of this year, the manufacture of 200-ton raw material billets was successfully achieved by using dozens of small slabs, group sealing and welding, and multiple constructions.

After that, the forged billet was successfully rolled on March 12th by the largest rolling ring rolling machine in the world. The austenitic stainless steel integral forging ring with a diameter of 15.8 meters and a single weight of 150 tons was successfully rolled. It not only realizes the densification and homogenization of large forgings, but also greatly reduces raw materials and energy consumption compared with traditional processes, and realizes “green forging”, which solves the urgent need for the manufacture of key components in the national heavy machine field.

This new technology has revolutionized the manufacturing process and process of steel ingot billets in the traditional heavy machinery industry, with excellent quality, environmental protection and energy saving.

At the same time, the mastery of super large ring rolling technology has also turned large ring forgings from split manufacturing to integral manufacturing. It has an important demonstration and leading role in the engineering field, and will provide more important tools for major engineers and major equipment in China in the future. Imaginative design space.